Stimulating device for enhancing release of negative air ions by a plant, and plant-based negative air ion producing device

ABSTRACT

A stimulating device for enhancing release of negative air ions by a plant includes a plant pot to receive a culture medium for cultivating the plant, and a negative voltage pulse module that outputs a negative voltage pulse to stimulate the plant via a pair of first and second conductive terminals. The first conductive terminal contacts the culture medium. The second conductive terminal is non-contact with the culture medium when the culture medium is placed in the plant pot.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority of Taiwanese Application No. 103112681,filed on Apr. 7, 2014.

FIELD

The disclosure relates to a negative air ion producing device, and moreparticularly to a plant-based negative air ion producing device.

BACKGROUND

The concentration of negative air ions (NAI) is an important index forevaluating air quality. Therefore, purely electrical NAI generators havebeen developed for indoor air purification. The NAI generated by suchdevices are different from plant-sourced NAI, which may be morebeneficial to health. However, under an ordinary environment, theability of a plant to release NAI is too weak to achieve a satisfactoryNAI concentration.

SUMMARY

Therefore, an object of the disclosure is to provide a stimulatingdevice for enhancing release of negative air ions by a plant.

According to one aspect of the disclosure, the stimulating deviceincludes a housing, a plant pot, first and second conductive terminalsand a negative voltage pulse module. The housing includes a firstsurrounding wall that defines an inner chamber. The plant pot isdisposed in the inner chamber, and is configured to receive a culturemedium for cultivating the plant. The first conductive terminal passesthrough the plant pot for contact with the culture medium. The secondconductive terminal is spaced apart from the first conductive terminal,is disposed on one of the housing and the plant pot, and is to benon-contact with the culture medium when the culture medium is placed inthe plant pot. The negative voltage pulse module is disposed on thehousing, includes a first electrode electrically coupled to the firstconductive terminal, and a second electrode electrically coupled to thesecond conductive terminal, and is configured to output a negativevoltage pulse at the first electrode so as to stimulating the plant viathe culture medium for enhancing release of the negative air ionsthereby.

Another object of the disclosure is to provide a plant-based negativeair ion producing device.

According to another aspect of the disclosure, the plant-based negativeair ion producing device includes a housing, a plant pot, a culturemedium, a plant, first and second conductive terminals and a negativevoltage pulse module. The housing includes a first surrounding wall thatdefines an inner chamber. The plant pot is disposed in the innerchamber. The culture medium is disposed in the plant pot. The plant iscultivated in the culture medium and releases negative air ions. Thefirst conductive terminal passes through the plant pot for contact withthe culture medium. The second conductive terminal is spaced apart fromthe first conductive terminal, is disposed on one of the housing and theplant pot, and is to be non-contact with the culture medium. Thenegative voltage pulse module is disposed on the housing, includes afirst electrode electrically coupled to the first conductive terminal,and a second electrode electrically coupled to the second conductiveterminal, and is configured to output a negative voltage pulse at thefirst electrode so as to stimulating the plant via the culture mediumfor enhancing release of the negative air ions thereby.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent inthe following detailed description of the embodiments with reference tothe accompanying drawings, of which:

FIG. 1 is a perspective view illustrating a first embodiment of theplant-based negative air ion producing device according to thedisclosure;

FIG. 2 is an exploded perspective view illustrating a stimulating deviceof the first embodiment;

FIG. 3 is a perspective view illustrating the stimulating device;

FIG. 4 is a sectional view of the stimulating device taken along lineII-II in FIG. 3;

FIG. 5 is a block diagram illustrating a negative voltage pulse moduleof the stimulating device;

FIG. 6 is a block diagram illustrating first and second electrodes ofthe stimulating device that have no direct electrical connectiontherebetween;

FIG. 7 is a block diagram illustrating the first and second electrodesof the stimulating device that have direct electrical connectiontherebetween;

FIG. 8 is a graph showing a record of the negative air ion concentrationresulting from a pot of Agave americana with use of the stimulatingdevice; and

FIG. 9 is a perspective view illustrating a stimulating device of thesecond embodiment of the plant-based negative air ion producing deviceaccording to the disclosure.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be notedthat like elements are denoted by the same reference numerals throughoutthe disclosure.

Referring to FIGS. 1 to 4, the first embodiment of the plant-basednegative air ion (NAI) producing device according to this disclosure isshown to include a stimulating device that includes a housing 1, a plantpot 2 filled with a culture medium (e.g., soil, culture liquid, etc.) inwhich a plant 100 may be cultivated, a first conductive terminal 22, asecond conductive terminal 14 and a negative voltage pulse module 3. Thehousing 1 has a first annular surrounding wall 12 that defines an innerchamber 121, a second annular surrounding wall 11 that surrounds thefirst annular surrounding wall 12, and an interconnecting wall 13 thatinterconnects bottom parts of the first and second annular surroundingwalls 12, 11. In this embodiment, the first conductive terminal 22passes through a bottom of the plant pot 2 for contact with the culturemedium. The second conductive terminal 14 is disposed on theinterconnecting wall 13 of the housing 1, and is exposed in the air andnon-contact with the culture medium when the culture medium is placed inthe plant pot 2. In addition, the housing 1 may further include a seat15 separably disposed under the interconnecting wall 13 foraccommodating the negative voltage pulse module 3 therein. In oneembodiment, the second conductive terminal 14 may be disposed on theplant pot 2 and is non-contact with the culture medium when the culturemedium is placed in the plant pot 2.

Referring to FIG. 1, in this embodiment, the plant 100 cultivated in theplant pot 2 belongs to Agavoideae, and is for example, Agave Americana.The plant of the Agavoideae subfamily is superior in the ability torelease NAI, drought resistance, shade resistance, etc., has a long lifespan (which may lead to longer time NAI release period), and grows wellindoors. High negative voltage pulses applied to the first conductiveterminal 22 (see FIGS. 2 and 4) may stimulate a root portion of theplant 100 via the culture medium, thereby enhancing release of NAI bythe plant 100. In one embodiment, the high negative voltage pulses mayrange between −4 KV and −20 KV and are applied with a frequency rangingbetween 0.5 Hz and 2 Hz.

Referring to FIG. 2, in this embodiment, the housing 1 further includesan annular bearing plate 17 that is separably mounted to the firstannular surrounding wall 12, that has an annular plate portion 173disposed between the first and second annular surrounding walls 12, 11and above the interconnecting wall 13, and a central opening 171corresponding in position to and in spatial communication with the innerchamber 121. The plate portion 173 of the bearing plate 17 cooperateswith the first annular surrounding wall 12, the second annularsurrounding wall 11 and the interconnecting wall 13 to form an outerchamber 16 thereamong, as shown in FIG. 4.

Further referring to FIG. 4, in this embodiment, the bearing plate 17has an annular engaging portion 172 that has an inverse-V-shaped crosssection, and that is hookably engaged with the first annular surroundingwall 12. In one embodiment, an outer peripheral part of the bearingplate 17 protrudes away from the interconnecting wall 13 and abutsagainst an inner surface of the second annular surrounding wall 11, suchthat the bearing plate 17 may be firmly mounted above theinterconnecting wall 13. When the plant pot 2 is placed in the innerchamber 121, a peripheral edge portion of the plant pot 2 that surroundsa top opening 23 of the plant pot 2 abuts against a top part of theengaging portion 172. The first annular surrounding wall 12 togetherwith the annular engaging portion 172 may provide sufficient structuralstrength for holding the plant pot 2 hanging in the inner chamber 121.

Referring to FIGS. 1-3, a bottom surface of the bearing plate 17 isformed with a plurality of through holes 174 for helping securing theother plants that may be cultivated in the outer chamber 16.

Referring to FIG. 5, the negative voltage pulse module 3 of thisembodiment includes a controller 31, an optical coupler 32 electricallycoupled to the controller 31, a driving circuit 33 electrically coupledto the optical coupler 32, a voltage pulse generating circuit 34 coupledto the driving circuit 33, and a pair of first and second electrodes301, 302. In one embodiment, the controller 31 may be implemented usingan STC11 series single-chip microcontroller. The controller 31 may beconfigured, according to an activation signal associated with an NAIconcentration and a continuous duration of NAI release stimulation thatare set via a remote controller 4 or a keyboard (not shown), to executetable look-up instructions and time setting instructions and output afirst control signal, such as a 5V pulse signal, based upon parametersobtained by execution of the instructions. The first control signal istransmitted to the driving circuit 33 via the optical coupler 32, whichmay provide good noise isolation between the controller 31 and thedriving circuit 33. The driving circuit 33 has a half-bridge chip 331that rectifies and amplifies the first control signal received from theoptical coupler 32 to provide a 5V pulse signal with a large current,thereby driving a MOSFET switch 332 to output to the voltage pulsegenerating circuit 34 a 12V modulation driving signal with a largedriving current. The voltage pulse generating circuit 34 includes aboost converter (T) that boosts a voltage level of the driving signal,and a rectifier circuit 340 that rectifies the boosted driving signal,so as to output the negative high voltage pulse to the first and secondelectrodes 301, 302, which are respectively coupled to the first andsecond terminals 22, 14 (see FIG. 2). The root portion of the plant 100is then stimulated by the negative high voltage pulse via the culturemedium and the first and second terminals 22, 14, thereby releasing NAImore efficiently. Since the housing 1 and plant pot 2 on which the firstand second terminals 22, 14 are disposed are not electrically coupledtogether, a virtual loop is formed via air between the first and secondelectrodes 301, 302 that have no direct electrical connectiontherebetween, and the plant 100 releases NAI to the air. In thisembodiment, the negative voltage pulse module 3 further includes aremote signal receiving circuit 35 configured to receive signals (e.g.,the activation signal) from the remote controller 4.

The boost converter (T) of the voltage pulse generating circuit 34includes a primary-side coil (N1) and a secondary-side coil (N2). Theprimary-side coil (N1) has a first terminal electrically coupled to thedriving circuit 33 for receiving the driving signal therefrom, and asecond terminal electrically coupled to a direct current voltage source342 via a resettable fuse 341. When overcurrent occurs in theprimary-side coil (N1), a resulted high temperature may cause theresettable fuse 341 to enter a non-conductive/electrically-isolatingstate, thereby protecting circuits from damage due to the overcurrent.Upon termination of the overcurrent and when the temperature becomeslower, the resettable fuse 341 may return to a conductive state. Thesecondary-side coil (N2) has a first terminal electrically coupled tothe first electrode 301, and a second terminal electrically coupled to acathode of a diode (D) that has an anode electrically coupled to thesecond electrode 302.

In this embodiment, the negative voltage pulse module 3 further includesa first resistor (R1) through which the first control signal is providedfrom the controller 31 to the optical coupler 32, and a second resistor(R2) electrically coupled between ground and a common node of the firstresistor (R1) and the controller 31. The voltage division by the firstand second resistors (R1), (R2) may effectively constrain a currentflowing into the optical coupler 32 at the time of activation, therebypreventing the optical coupler 32 from damage due to an excessively highvoltage provided by the controller 31.

When the root portion of the plant 100 is stimulated by the highnegative voltage pulse, electrical discharge may occur at leaf tips ofthe plant 100. In order to prevent persons/animals from being frightenedupon touching the leaf tips, the negative voltage pulse module 3 of thisdisclosure may further include at least one proximity sensor 36 (e.g.,an ultrasonic proximity sensor) disposed on, for example, the secondannular surrounding wall 11 of the housing 1, and electrically coupledto the controller 31, as shown in FIGS. 3 and 5, to thereby form anultrasonic fence around the plant 100. When the proximity sensor 36senses the presence of an object within a predetermined distance range,e.g., a 20 cm range, the proximity sensor 36 generates a second controlsignal that is provided to the controller 31 and that causes thecontroller 31 to stop output of the first control signal, so that thedriving circuit 33 stops driving the voltage pulse generating circuit 34to generate the negative high voltage pulse. In this embodiment,multiple proximity sensors 36 that are disposed apart from each other onand around the second annular surrounding wall 11 are provided.

Even if the voltage pulse generating circuit 34 stops output of thenegative high voltage pulse, electric charges may remain on the leaftips of the plant 100. In order to further prevent persons/animals frombeing frightened upon touch, the voltage pulse generating circuit 34 mayfurther include a third resistor (R3) electrically coupled between thefirst and second electrodes 301, 302. By virtue of the third resistor(R3), the remaining electric charges may be discharged through adischarging loop formed by the first electrode 301, the third resistor(R3) and the second electrode 302, thus preventing occurrence ofelectric shocks. In one embodiment, the third resistor (R3) has aresistance of 1100 M ohms.

In this embodiment, the stimulating device further includes atemperature and humidity sensor 37, a humidifier 38 (including ahumidifier control circuit), and a fan device 39 (including a fancontrol circuit) that are disposed on the housing 1 and are electricallycoupled to the controller 31. The temperature and humidity sensor 37provides to the controller 31 a set of ambient temperature and humidityvalues sensed thereby. The controller 31 may control, according to adifference between a set of preset temperature and humidity values andthe set of ambient temperature and humidity values sensed by thetemperature and humidity sensor 37, operation of the humidifier 38 and aspeed and a direction of wind provided by the fan device 39, to therebymake the ambient temperature and humidity approach the presettemperature and humidity values, which is usually set as being suitablefor the presence of NAI.

In this embodiment, the humidifier 38 and the fan device 39 are disposedabove the plant pot 2, and a spray outlet of the humidifier 38 facestoward a front side of the stimulating device, so that the sprayprovided by the humidifier 38 may be directly blown into the air by thefan device 39, thereby avoiding adhesion of the spray on the stimulatingdevice which may otherwise lead to safety concerns, such as currentleakage.

In this embodiment, the stimulating device further includes an NAIdetector 51 that detects a concentration value of ambient NAI and thatis electrically coupled to the controller 31 for providing thereto theconcentration value of ambient NAI thus detected. The controller 31 maydetermine, according to a difference between a preset concentrationvalue of NAI and the concentration value of ambient NAI detected by theNAI detector 51, whether or not to generate the first control signal, tothereby maintain the concentration of ambient NAI within an appropriaterange. The temperature sensor 37, the humidifier 38, the fan device 39and the NAI detector 51 may be integrated as a spatial NAI homogenizingdevice.

According to experiments, when the second annular surrounding wall 11 isspaced apart from the plant pot 2 by a distance that ranges between 50mm and 200 mm such that the first and second electrodes 301, 302 are notelectrically coupled together through connection between the housing 1and the plant pot 2 (see FIG. 6), the NAI concentration measured at alocation about 1 meter apart from the housing 1 is approximately 50,000ions/cm³. On the other hand, when the first and second electrodes 301,302 are electrically coupled together via a wire between the housing 1and the plant pot 2 (see FIG. 7), the NAI concentration measured at thesame location is approximately 3,000 ions/cm³. It is thus apparent thatby virtue of the plant pot 2 being disposed in the inner chamber 121 ofthe housing 1, making the first and second electrodes 301, 302 nothaving direct electrical connection therebetween, the plant 100 mayrelease NAI more efficiently, thereby promoting indoor NAIconcentration.

FIG. 8 is a graph showing a record of the NAI concentration resultingfrom a pot of Agave americana stimulated by the negative high voltagepulse using the embodiment of the stimulating device according to thisdisclosure.

Referring to FIG. 9, in the second embodiment of the NAI producingdevice of this disclosure, the housing 1 may be configured for placing,in addition to the plant pot (not shown) configured for NAI releasestimulation (e.g., a plant pot 2 in which a plant of the Agavoideaesubfamily is cultivated, as shown in FIG. 1), multiple planters (notshown) each being smaller than the plant pot. Note that the planters maybe used to cultivate plants of the Agavoideae subfamily or other kindsof plants therein. The second embodiment further differs from the firstembodiment in that in lieu of the central opening 171 and the throughholes 174 (see FIG. 2), the bearing plate 17′ has a primary opening 175that is spatially connected to the inner chamber 121 and that isconfigured for holding the plant pot, and multiple smaller secondaryopenings 176 that are configured for holding the planters. Each of thesecondary openings 176 is in spatial connection with the outer chamber16, so that a respective planter may be held in the outer chamber 16. Inthis embodiment, the secondary openings 176 are arranged in a vicinityof the primary opening 175.

In summary, by virtue of the first and second conductive terminals 22,14 that are respectively disposed on the plant pot 2 and the housing 1and that have no direct electrical connection therebetween, a virtualloop may be formed via the air between the first and second electrodes301, 302, thereby stimulating the plant 100 to enhance its NAI release,so as to promote indoor NAI concentration. In addition, the design ofthe proximity sensor 36 and the third resistor (R3) may preventpersons/animals from suffering electric shocks when touching the plant100. Through the design of the temperature and humidity sensor 37, thehumidifier 38, the fan device 39 and the NAI detector 51, the ambientNAI concentration may be properly adjusted via the controller 31, tothereby maintain the ambient NAI concentration within an appropriaterange, and air quality may thus be improved.

While the disclosure has been described in connection with what is(are)considered the exemplary embodiment(s), it is understood that thisdisclosure is not limited to the disclosed embodiment(s) but is intendedto cover various arrangements included within the spirit and scope ofthe broadest interpretation so as to encompass all such modificationsand equivalent arrangements.

What is claimed is:
 1. A stimulating device for enhancing release ofnegative air ions by a plant, said stimulating device comprising: ahousing including a first surrounding wall that defines an innerchamber; a plant pot disposed in said inner chamber, and configured toreceive a culture medium for cultivating the plant; a first conductiveterminal passing through said plant pot for contact with the culturemedium; a second conductive terminal spaced apart from said firstconductive terminal, disposed on one of said housing and said plant pot,and to be non-contact with the culture medium when the culture medium isplaced in said plant pot; and a negative voltage pulse module disposedon said housing, including a first electrode electrically coupled tosaid first conductive terminal, and a second electrode electricallycoupled to said second conductive terminal, and configured to output anegative voltage pulse at said first electrode so as to stimulating theplant via the culture medium for enhancing release of the negative airions thereby.
 2. The stimulating device according to claim 1, wherein:said housing further includes a second surrounding wall surrounding saidfirst surrounding wall, and an interconnecting wall interconnectingbottom parts of said first and second surrounding walls; said secondconductive terminal is disposed on said interconnecting wall of saidhousing, and is to be exposed in air when the culture medium is placedin said plant pot; and said first conductive terminal passes through abottom of said plant pot.
 3. The stimulating device according to claim2, wherein said housing further includes a bearing plate that has aplate portion separably disposed between said first and secondsurrounding walls and above said interconnecting wall, and that has acentral opening in spatial communication with said inner chamber, saidplate portion of said bearing plate cooperating with said firstsurrounding wall, said second surrounding wall and said interconnectingwall to form an outer chamber thereamong.
 4. The stimulating deviceaccording to claim 3, wherein said bearing plate has a bottom surfacethat is formed with a plurality of through holes, and an engagingportion that is hookably engaged with said first surrounding wall, saidplant pot having a peripheral edge portion that abuts against a top partof said engaging portion, thereby hanging on said bearing plate.
 5. Thestimulating device according to claim 3, wherein said bearing plate hasa bottom surface that is formed with an opening in spatial connectionwith said outer chamber for holding a planter.
 6. The stimulating deviceaccording to claim 1, wherein said negative voltage pulse moduleincludes: a controller disposed to receive an activation signal andconfigured to generate a first control signal according to theactivation signal; an optical coupler electrically coupled to saidcontroller for receiving the first control signal therefrom; a drivingcircuit electrically coupled to said optical coupler for receiving thefirst control signal therethrough, and configured to generate a drivingsignal according to the first control signal; and a voltage pulsegenerating circuit electrically coupled to said driving circuit forreceiving the driving signal therefrom and configured to generate thenegative voltage pulse according to the driving signal.
 7. Thestimulating device according to claim 6, wherein said voltage pulsegenerating circuit includes: a boost converter including a primary-sidecoil and a secondary-side coil, said primary-side coil having a firstterminal that is electrically coupled to said driving circuit forreceiving the driving signal therefrom, and a second terminal, saidsecondary-side coil having a first terminal that is electrically coupledto said first electrode, and a second terminal; a resettable fuseelectrically coupling said second terminal of said primary-side coil toa direct current voltage source; and a diode having a cathode that iselectrically coupled to said second terminal of said secondary-sidecoil, and an anode that is electrically coupled to said secondelectrode.
 8. The stimulating device according to claim 6, wherein saidnegative voltage pulse module further includes a first resistor throughwhich the first control signal is provided from said controller to saidoptical coupler, and a second resistor which electrically couples acommon node of said first resistor and said controller to ground.
 9. Thestimulating device according to claim 6, further comprising: a proximitysensor disposed on said housing, electrically coupled to saidcontroller, and configured to generate, upon detecting presence of anobject within a predetermined distance range, a second control terminalthat is provided to said controller and that causes said controller tostop output of the first control signal, so that said driving circuitstops driving said voltage pulse generating circuit to generate thenegative voltage pulse.
 10. The stimulating device according to claim 6,further comprising a temperature and humidity sensor, a humidifier, afan device and a negative air ion detector, each of which is disposed onsaid housing and is electrically coupled to said controller, wherein:said temperature and humidity sensor is configured to provide to saidcontroller a set of ambient temperature and humidity values sensedthereby; said negative air ion detector is configured to provide to saidcontroller a concentration value of ambient negative air ions detectedthereby; and said controller is further configured to control, accordingto a difference between a set of preset temperature and humidity valuesand the set of ambient temperature and humidity values sensed by saidtemperature and humidity sensor, operation of said humidifier and aspeed and a direction of wind provided by said fan device, and todetermine, according to a difference between a preset concentrationvalue of negative air ions and the concentration value of ambientnegative air ions detected by said negative air ion detector, whether ornot to generate the first control signal.
 11. The stimulating deviceaccording to claim 1, further comprising a resistor electrically coupledbetween said first and second electrodes.
 12. A plant-based negative airion producing device, comprising: a housing including a firstsurrounding wall that defines an inner chamber; a plant pot disposed insaid inner chamber; a culture medium disposed in said plant pot; a plantcultivated in said culture medium and releasing negative air ions; afirst conductive terminal passing through said plant pot for contactwith said culture medium; a second conductive terminal spaced apart fromsaid first conductive terminal, disposed on one of said housing and saidplant pot, and to be non-contact with said culture medium; and anegative voltage pulse module disposed on said housing, including afirst electrode that is electrically coupled to said first conductiveterminal, and a second electrode that is electrically coupled to saidsecond conductive terminal, and configured to output a negative voltagepulse at said first electrode so as to stimulating said plant via saidculture medium for enhancing release of the negative air ions thereby.13. The plant-based negative air ion producing device according to claim12, wherein said plant belongs to the subfamily of Agavoideae.
 14. Theplant-based negative air ion producing device according to claim 13,wherein said plant is Agave americana.